No, not all longitudinal waves can be termed as sound. Sound specifically refers to the propagation of longitudinal waves through a medium, typically air or other gases, liquids, or solids. These waves are generated by the vibration or oscillation of particles in the medium.
While sound waves are a type of longitudinal wave, not all longitudinal waves are sound waves. Longitudinal waves are characterized by the vibration of particles in the same direction as the wave is traveling. They have regions of compression and rarefaction as they propagate through the medium.
Examples of other longitudinal waves that are not considered sound waves include seismic waves (such as P-waves and S-waves) that travel through the Earth during an earthquake, and pressure waves in fluids, such as water waves or waves in a spring.
So, while all sound waves are longitudinal waves, not all longitudinal waves can be categorized as sound waves.